Pope Dionysius was the Bishop of Rome from 22 July 259 to 26 December 268. His pontificate oversaw the transition from Valerian's persecutions to the toleration issued by Gallienus in 260. During this
Portrait of Dionysius, by the 15th c. artist Sandro Botticelli, in the Sistine Chapel. Dionysius is depicted in anachronistic papal vestments, along with a book, common attributes in art of this pope.
A bas relief of Emperor Valerian standing at the background and held captive by King of Kings Shapur I found at Naqsh-e Rustam, Shiraz, Iran. The kneeling man is probably Philip the Arab.